Photographic camera with automatic exposure control



P 1963 NAYUKl OHARA 3,103,149

PHOTOGRAPHIC CAMERA WITH AUTOMATIC EXPOSURE CONTROL Filed Dec. 28. 19608 Sheets-Sheet 1 Sept. 10, 1963 NAOYUKI OHARA 3,103,149

PHOTOGRAPHIC CAMERA WITH AUTOMATIC EXPOSURE CONTROL Filed Dec. 28. 19608 Sheets-Sheet 2 Fi g 4 AUTO 22|6l| 85642-82 [H 5002501256030 |5 8 4 2 1B Sept. 10, 1963 NAOYUKI OHARA 3, PHOTOGRAPHIC CAMERA WITH AUTOMATICEXPOSURE CONTROL Filed Dec 28, 1960 a SheetsSheet 5' Sept. 10, 1963NAOYUKI OHARA 3,1 PHOTOGRAPHIC CAMERA WITH AUTOMATIC EXPOSURE CONTROLFiled Dec. 28. 1960 s Sheets-Sheet 4 2 m L I-'' 15 l Se t. 10, 1963 INAGYUKI OHARA 3,103,149

Filed Dec. 28. 1960 PHOTOGRAPHIC CAMERA WITH AUTOMATIC EXPOSURE CONTROL8 Sheets-Sheet 5 1 59 64 65 6 10 617 j a a 66 7 66 Se t. 10, 1963NAOYUKI OHARA 3,

PHOTOGRAPHIC CAMERA WITH AUTOMATIC EXPOSURE CONTROL 8 Sheets-Sheet 6Filed Dec. 2 1960 Se t. 10, 1963 NAOYUKI OHARA 3,103,149

PHOTOGRAPHIC CAMERA WITH AUTOMATIC EXPOSURE CONTROL Filed Dec, 28. 1960s Sheets-Sheet '7 F59 J2 11a 9s- 62 iidfl) .Sept. 10, 1963 NAOYUKI OHARAI 3, 9

PHOTOGRAPHIC CAMERA WITH AUTOMATIC EXPOSURE CONTROL Filed Dec. 28. 19608 Sheets-Sheet 8 a ma United States Patent PHOTOGRAPHIC CAMERA WITHAUTOMATIC EXPOSURE CONTROL Naoyuki Ohara, 436 l-chome, Seshigaya,Setagaya-lru,

Tokyo-t0, Japan Filed Dec. 28, 1960, gar. No. 79,046 Claims priority,application Japan Oct. 20, 1960 3 Claims. (Cl. 95-40) This inventionrelates to photographic cameras, and more particularly it relates to acamera with a built-in exposure meter and with automatic control ofexposure.

It is an object of the present invention to provide a photographiccamera with automatic exposure control which is of greatly improvedconstruction and is extremely positive in operation.

It is another object of the invention to provide a camera for manualselection of diaphragm setting and as a member for switching over toautomatic control; the switching over of the said member from manual toautomatic operation is caused to be possible only during a presetexposure time within a certain limited range within the exposure time(shutter speed) which is adjustable by the aforesaid shutter speedsetting member; and the shutter speed selection after the said switchingover is caused to be regulated within a limited range, whereby theautomatic control of exposure can be efiected in an extremely simple andpositive manner.

It is a further. object of the invention to provide a socalledsingle-lens'reflex camera which embodies the abovedescribed camera withautomatic exposure control, and wherein a rotatably supported bladeopening member is disposed coaxially about the optical axis and causedby the charging or cocking thereof to open the blades in a preparatorymanner prior to the opening and closing of the blades for the originalpurpose of photography, thereby enabling the adjustment of focus throughthe lens system; or a single-lens reflex camera of the so-calledquick-return mirror type wherein, by charging or cocking the aforesaidblade opening member immediately after the opening and closing of theblades for the original purpose of photography, the reopening of theblades is made possible.

It-is yet a further object of the invention to provide a camera withautomatic exposure control which possesses the various [features ofperformance as described'above yet has a simple and easily andeconomically fabricated construction.

The manner in which the foregoing objects, other objects, and advantagesmay best be achieved, as well as the details of the invention, will beunderstood more fully from a consideration of the following description,taken in conjunction with the accompanying drawings of a fewrepresentative embodiments of the invention in which the same orequivalent parts are designated by the same reference numerals orletters, and in which:

FIG. 1 is an exploded perspective view for an explanation of theprinciple of the invention;

FIG. 2 is a front elevational view, showing one embodiment of theinvention as applied to a single-lens reflex of interchangeable lenstype;

FIG. 3 is a rear elevational view of the embodimentof FIG. 2;

FIG. 4 is a plan or topview of the embodiment of FIG. 2; 1 j r FIG. 5 isa sectional View, taken on a vertical plane passing through the opticalaxis, of theembodiment of FIG. 2;

FIG. 6 is a perspective view showing the exterior of a representativeembodiment of an interchangeable lens assembly according to theinvention;

FIG. 7 is a sectional view, taken on a vertical plane passing throughthe optical axis, of the embodimentuof FIG. 6;

FIG. 8 is schematic diagram, partly in section, showing the essentialmem-bersof the diaphragm mechanism for a lens according to theinvention;

FIG. 8a, FIG. 8b, and FIG. Scare front elevational views of theessential members of the mechanism shown inF'IG. 8;

FIG. 8d is an edge View of FIG. 8b; FIG. 9 is a front elevational view,partly in section, showing a diaphragm mechanism for a lens;

FIGS. 10 through 13 are diagrams indicating the positional relations ofcertain members of the diaphragm mechanism relative to the camera body;

FIGS; 14 andlS are plan or top views, partly in section and with partscut away, showing the mutual relationship between the shutter speedsetting member and the diaphragm setting member of one embodiment of theinvention 'at the time of switching between manual and auto.- maticoperation; and

FIGS. 16 and 17 are plan or top views, partly in section and with partscut away, showing the mutual relationship between the shutter speedsetting member and the diaphragm setting member of another embodiment ofthe invention at the time of switching between manual and automaticoperation.

The principal aspects of the princple of the invention will be explainedin the following description with reference to FIG. 1. A shutter bladeopening member 1 is disposed in a rear position as shown. A diaphragmblade opening member 3, which is provided with a clockwise rotatingtorque by a spring 6, has a latching pawl 4 at the top thereof which iscomovably contacting a forwardly extending lug 2 of the blade openingmember 1. At a forward part of the mechanism, a first diaphragmactuating member 7, which is provided with a clockwise rotating torqueby a spring 9, has a pawl 8 provided thereon which is comovablycontacting a forwardly extending lug 5 of the diaphragm blade openingmember 3.- Said first diaphragm actuating member 7 and a seconddiaphragm actuating member 10, together, support there- 'between severaldiaphragm blades (not shown) in such a manner as to enable the actuationof said blades. The said second diaphragm actuating member 10 is alsoprovided with a clockwise rotating torque by a spring 13. The memberdesignated by the reference numeral 11 is a pawl which is so mounted asto slide a predetermined distance relative to the second diaphragmactuating member 10 and is pulled to a fixed position by a spring 12which is stronger than the spring 13 :for the second diaphragm actuatingmember 10. The actuation of the diaphragm will be more clearlyapparent'from the description which will be given presently.

A diaphragm setting ring 14 is disposed behind the aforesaid firstdiaphragm actuating member 7 and is pro- I vided with a forwardlyextending lug 15 which, acting through the pawl 11 of the afgresaidsecond diaphragm actuating member 10, arrests the rotation due to thespring 13 of the said member 10. In the vicinity of the outer side ofthecalibration for minimum diaphragm opening of the diaphragm scale on thisring 14, an automaticoperation mark A is inscribed in alignment for theswitching of the Y diaphragm control from manual adjustment to automaticcontrol or the reverse. A common index 16a is provided for both thediaphragm scale and the automatic operation mark A. A shutter speedsetting ring 17 for the selection of shutter speed is disposed betweenthe ring 14' and member 3, and its scale reading is indicated by anindex 1611*. It is possible to adapt this index 16b so that it willfunction doubly as also the aforesaid index 16a. A correction ring 18for correcting a built-in exposure meter in accordance with variousphotographic factors is disposed between the aforementioned bladeopening member 1 anddiaphragm blade opening member 3. In accordance withsuch fac- "tors as the'film sensitivity and film factor, the coupledposition of this correction ring 18 relative to the shutter speedsettingring 17 is varied by reengaging the click detent spring 19 whichis fixed to the said ring 18 and is engageable with calibrated notchescut in the said ring 17. A correction lever 21, which is fixed to oneend of a shaft 22 and caused to have a tension-maintained torque tending to rotate it in the counterclockwise direction, has at a cam surface20* on the aforesaid correction ring 18.

throughthe shaft 22 to its other end, then through a gear train 23, 214,25, and 26 to'cause an exposure meter 27, itself, to rotate, withoutcausing variation in the deflection angle of the exposure meter pointer28 produced independently by the exposure meter 27 in response to'thebrightness of the object being photographed.

-. A-coupling gear 30 1s intermeshed with a gear tooth portion on thediaphragm blade opening member 3 and i its tip a pin which is inelastically-maintained contact with I rotates a coupling shaft 31 towhich it is fixed. -At the other end of-the coupling shaft 31, itsmovement is transmitted through a gear train 32, 33, 3'4, 36, and 38,which iscoupledthereto by a clutch mechanism 37, and through a rack 39to actuate a coupling cam plate 40; which is installedto confront andfunction in cooperation with the exposure meter pointer '28.

On one hand, a cam (not shown) having cam action in the direction-of theoptical axis .is provided on the reverse surface of the diaphragmsetting ring 14. One end of a switching rod 42, which is movable in thedirection of I tinually pressed against the aforesaid cam surface on thereverse surface of the diaphragm setting ring 14. Accordingly, when thediaphragm aperture scale on the diaphragm settingring 14- is positionedso that the setting members, and not the mark A, coincide with the index1611, the switching rocl 42 is pushed downward by the said cam on thereverseside, and this movement is transmitted through the clutch lever43 to disengage the clutch 37.

Since this disengagement of the clutch 37 causes the movement of the,coupling gear 30, which is intermeshed with the gear tooth portion ofthe diaphragm blade opening ring 3, to be cut off, it is then unable toactuate the coupling cam 40', which is then returned by its own spring41 'to its starting position to await subsequent action and the exposureis manually controlled until the setting ring is returned to theposition where A. coincides with index 16a.

When the automatic operation mark A of the diaphragm setting ring 14 ismade to coincide with the index 16a, the switching rod 42 is pushed outforward by the rear cam (not shown) and spring 35, whereby the clutch 37is clutched by way of the clutch lever 43. In this state, when the bladeopening member 1 is rotated counterclockwise in order to charge, the lug2 is accompanied by the blade opening member 3 and the lug 5 of saidblade opening member 3 is accompanied by the first diaphragm actuatingmember 7 so as to rotate the said member 7 in the same direction,whereby the diaphragm blades are wholly opened.

member 1 is locked at its charged state. When the said blade openingmember 1 commences to rotate clockwise by camera release operation, thediaphragm opening member 3 commences to follow the movement of the saidblade-opening member 1 byits spring 6. At the same time, because ofengagement of the coupling gear 30 with the diaphragm operating member3, the coupling cam 40 which has been ready for operation is lowered inaccordance with said following movement of the diaphragm opening member3 by way of the coupling shaft 31, gear train (32, 33, 34, 36, 38, 39)and the clutch 37. On the other hand, the coupling gear 30 itself, isrotated in accordance with the selected shutter speed and exposure indexof the used film and is oscillated in accordance with brightness of theobject obtained by the exposure meter the position of which has beendetermined. In this state, the said following movement of the diaphragmopening member 3 continues until the loweringmovement of the saidcoupling cam 40 is stopped by the stopped pointer 23. Accordingly, thefirst diaphragm actuating member cooperating with the said diaphragmopening member (3 'a photographing of one time. Even in the case of thesame photographing condition, when a film having a different lightsensitivity and a different shutter speed is selected, correspondingcompensation is given by the selfrotation of the exposure meter, so thatthe obtained diaphragm opening aperture is always correct. This fact canbe understood from the above detailed description relating to exposureautomatic control.

In the case of manual selection of the diaphragm, a desired diaphragmvalue among the diaphragm dial markings of the diaphragm setting ring ll is made to coincide with the mark 16a, whereby the switching rod 42 ispressed downward by the rear cam, thus causing release of the clutch androtation of the second diaphragm actuating member 10 against the spring13 through the pawl 11' of the said member 1 0. In this state, when theblade opening ring 1 is rotated counterclockwise to lock the camera, thediaphragm blades are totally opened in the same manner as the case ofthe above-mentioned automatic control, whereby the said ring 1 isbrought in its locked state. When the said ring 1 is made to be restoredclockwise by means of the camera release, the diaphragm opening member 3and first diaphragm actuating member.

7 follow the restoration movement of the said ring 1 by way of therestoring springs d and 9 and the gear 30 being in engagement with thediaphragm opening member 3 is also rotated. However, since the clutch 37is not engaged, the coupling cam 4th does not start, so that it has norelation to the exposure pointer 28 and carries out the same process asthat of the said ring 1',wher'eby the diaphragm aperture selected by thediaphragm scale ring 14 is obtained. According to the above description,

it will become clear that automatic control and manual operation of theexposure can be sufficiently and. surely carried out in accordance withthe principle-of FIG. 1 of this invention.

Referring now to FIGS. 2 through 8, wherein is illustrated oneembodimentof the invention as applied to an In this time, the said blade openingc) interchangeable-lens type, single-lens reflex camera, the referencenumeral 50 designates the front plate of the camera, to the frontsurface of which a shutter body 51 capable of performing the operationsnecessary for a single-lense reflex camera is mounted, and a bayonetmount -3 is fixed through the interposition of an intermediate ring 52..A connection terminal, that is, a plug 54 for the electric circuit forflash photography is likewise mounted on the front plate 50. (A separatepatent application for a representative shutter 51 has already beenfiled by the present applicant: US. patent application, Serial No. 15,-863, May 18, 1960, Naoyuki Ohara, Lens Shutter for Single-Lens ReflexCamera, froma consideration of which the following description will bemore clearly apparent.)

The blade opening member 1 is charged, or cocked, in clockwise directionby an actuating pin 1a and is locked in thecharged, or cocked, positionby the engagement of a cut-out 1b formed thereon by a latch pawl 55which has elastic torque in the clockwise direction. A camera release.button 56 is provided on the camera body side. When this button 56 ispushed, its movement is transmitted by its extension end, through anintermediate lever 57, to cause a trigger release lever 58 to releasethe aforesaid latch pawl 55, which is looking the blade opening member 1in its cocked position, from the cut-out 1b. When a release lever 59,which is disposed coaxially with the latching pawl 55 is released by aprotruding tooth on the blade opening member 1, it is pushed back to theposition illustrated and releases the shutter in this position,;wherebythe opening and shutting of the shutter blades for exposure areaccomplished. Referring to FIGS. 4' and 5, the chain line with two dotsindicates the outline of an interchangeable lens assembly 60, which isattached to the camera by the engagement of a bayonet lug -61 on thelens side with the bayonet mount 53 onthe camera side. The externalappearance and the internal construction of the lens assembly areillustrated in detail in FIGS. 6 and 7. These details and therelationsat the time of changing lenses will be more apparent from adescription to follow presently.

On the basis of the above description of various members, the operationof the camera of the present invention will be best understood from thefollowing description, when read in connection with FIGS. 1 through 8,which illustrate the principle of the invention and one embodiment ofthe invention as applied to a single-lens reflex camera "ofinterchangeable lens type.

When the diaphragm scale range of the diaphragm setting ring 14 isconfronting the index 16a in the condition wherein selection of thediaphragm setting can be accomplished, the camera is a manually operatedcamera wherein the diaphragm and the shutter speed can each be adjustedindependently. Then, when the automatic operation mark A onthe diaphragmsetting ring 14 is brought to coincide with the index 16a, the camerabecomes an automatically operated camera wherein the diaphragm settingis automatically adjusted in accordance with the speed selection of theshutter speed setting ring 17 with re spect to the index 16b.

Referring to FIG. 1, when the automatic operation mark A of thediaphragm setting ring 14 is brought to coincide with the index 16a, theswitching rod 42 is actuated by the cam (not shown) on the reversesurface of the diaphragm setting ring 14 and causes the clutch 37 in thecoupling gears 36 and 38 to engage. Then, when the blade opening member1 is rotated in the counterclockwise direction and cooked, its movementis transmitted through an intermediate device (not shown) to open theshutter blades fully and, at the same time, to cause the diaphragm bladeopening ring 3 to move in unison. The said ring 3 causes, through itsforwardly extending lug 5, the first diaphragm actuating member 7 tomove in unison, and the diaphragm blades 64 are fully opened by theactuation due to the said member 7. Thus, the camera is able to adjustits focus as a single-lens reflex camera. At the same time, the rotationof the diaphragm blade opening member 3 is transmitted through thecoupling gear 30 intermeshed with the gear tooth portion ofsaid member3, through the coupling shaft 31 which is the rotational shaft of thesaid gear 30, through the gear train 32, 33, 34, 36, and 38, and thenthrough the rack 39 to cause the coupling cam 4% to be in a preparatoryposition for starting with respect to the exposure meter pointer 28. Inthis case, however, the special amount of rotation -(F:22 to mark A)necessary for the switching of the diaphragm setting ring 14 forswitching the camera to automatic control must not change the limitingposition of the degree of opening of the diaphragm which has alreadybeen set. That is, for this requirement, the movement of the forwardlyextending lug 15 accompanying the said special amount of rotation doesnotparticipate at all in the operation of the second diaphragm actuatingmember 10 and is limited in moving only the pawl 11. Otherwise, themutually relative positions of the two diaphragm actuating members (7and 10) will be disturbed, and the diaphragm aperture will be changed.For this purpose, the pawl 11 of the second diaphragm actuating member10 is adapted to operate with respect toonly the aforesaid specialamount of rotation of the diaphragm setting ring 14, independently ofthe actuating member 10, to maintain the limiting value of the diaphragmaperture.

On the other hand, when the automatic operation mark A is separated fromthe index 16a and the diaphragm setting ring 14 is turned to a diaphragmscale position in order to switch the automatic control condition of thecamera to manual control condition, the pawl 11 which follows up themovement of the forwardly extending lug 15 returns once to the positionindicated in the drawing, independently of the second diaphragmactuating member 10, and thereafter moves in unison with the seconddiaphragm actuating member 10 in accordance with the selection of thediaphragm setting.

It will be obvious from the above description that, when the automaticoperation marker A of the diaphragm setting ring 14 is brought tocoincidence with the index 16a, and the blade opening member 1 isrotated counterclockwisely to cock it, the system illustrated in FIG. 1is in the following state. That is, the coupling cam 40 which isprovided to confront and operate cooperatively with the exposure meterpointer 28 is placed in the starting position awaiting operation, andthe second diaphragm actuating member 10 is stopped in the limitingposition for minimum diaphragm aperture, but the diaphragm blades 64 aremaintained fully open by another means, that is, by the aforesaid firstdiaphragm actuating member 7, and the shutter blades 68 are similarlymaintained fully opened by the shutter blade opening member 1. 1f, underthese conditions, the first diaphragm actuating member 7 is rotatedclockwisely, diaphragm blades will be stopped down until, at the end oftheir movement, they will attain their minimum aperture condition forthe first time. Accordingly, by stopping the diaphragm actuating member7 at any suitable point of this movement, it is possible to obtain anydesired diaphragm aperture.

Next, when the click spring 19 is set on the film exposure indexscale onthe shutter speed setting ring 17 in accordance with the exposure indexof the film used, and the said ring 17 is subjected to the notation forselection of the shutter speed, the correction ring 18 is rotated inunison by the click spring 19, and the correction lever 21 which is inelastically-maintained contact .with the cam surface 20 of the said ring18 is caused to rotate with the correction shaft 22 as the center ofrotation. This movement is transmitted through the gear train 23, 24,25, and 26 to rotate the exposure meter itself, and, without chan-g ingthe angular displacement of the exposure meter pointer 28 due to theresponse of the brightness of the object being photographed, theposition of the said exposure speed, etc.)

meter pointer 28 is varied according to the corrected sensitivity (dueto the film sensitivity, filter factor, and shutter Accordingly, theappropriate diaphragm setting is exhibited with respect to the steppededge of the coupling cam 40 which is installed to confront the positionof the exposure meter pointer 28, and which is awaiting operation in thestarting position.

If, in this condition, that is, in the case of an automatic exposurecontrol camera, the camera shutter is released by means of the bodyrelease button 56, the movement of the said bottom 56 will betransmitted through the intermediate lever 57 and release lever 58 todisengage the latch pawl 55 from the cutout 1b in the blade openingmember 1. Consequently, the blade opening member 1 will begin to returnin the clockwise direction. First, the

I shutter blades are closed, then the rotational movement in theclockwise direction of the diaphragm blade opening member 3 which isbeing returned by the spring 6 is transmitted through the coupling gear34 coupling shaft v31, gear train 32, 33, 34, 36, and 38 and rack 39-andproceeds until the couplingcam 40 is stopped by the exposure meterpointer 28, which, being held fixed in its indicated position at thebeginning of the release operation, acts as a stopper. Thus, thelimiting stop position for the clockwise rotation of the first diaphragmactuating member 7 due to the force of the spring 9 of the said member 7is determined; the diaphragm blades 64 are stopped down to theappropriate diaphragm aperture; and the so-cal-led automatic diaphragmcontrol due to an ex posure meter is achieved. v

Furthermore, in the case of a single-lens reflex camera, the opening andshutting of the shutter blades for the purpose of exposure isaccomplished when, after the mirror and film cover plate, which had beencovering the film, have been raised by a known method, the shutterrelease lever 59 is released by the action of the protrusion 10 on theblade opening member 1 accompanying the return movement of the saidmember 1 to its initial position.

Next, in the case wherein the present camera is to be used as aso-called manual-operation camera in which the diaphragm setting may beselected manually, the diaphragm setting ring 14 is rotated,displacing'the automatic operation mark A from the index 161:, and thedesired diaphragm setting is manually selected. Since this operationcauses the cam (not shown) on the reverse surface of the diaphragmsetting ring 114 to push the switching rod 42 downwardly, the clutchlever t3 rotates counterclockwisely against the force of the spring 35.Consequently, the clutch 37 is disengaged, and the coupling between thegear 36 and the gear 38 is cut. Then, when the camera shutter isreleased, the clockwise rotation of the diaphragm opening member 3,which is caused to return by the spring 6, is not limited by theexposure meter pointer 28. Therefore, together with the firstdiaphragmactuating member 7, the said member 3 operates through its own maximumoperating angle.

On one hand, the forwardly extending lug of the diaphragm setting ring14 determines the rotational position to which the second diaphragmactuating member '10 is rotated clockwisely and returned by the spring13. The second diaphragm actuating member "10 stops at thisposiextending in a direction which is substantially tangential to thecenter hole of the said diaphragm actuating member. (This feature iscovered by the patent application already filed by the presentapplicant: U.S. patent application, Serial No; 17,695, March 25, 1950,Maoyuki Ohara, Device for Visually Verifying the Depth of Field for LensShutters of Single-Lens Reflex Cameras, which should be referred to forfurther details.)

When the blade opening member 1 is cooked, the movement is transmittedthrough an intermediate device (not shown) to open the shutter bladesfully, similarly as in the case of the automatic exposure controlcamera. Atthe same time, this movement is transmitted through thediaphragm blade opening member 3 to rotate in unison the firstdiaphraghm actuating member 7 and to open the diaphragm blades 64 fully,thereby making possible the adjustment of focus as a single-lens reflexcamera.

In this condition, that is, in the case of a manual exposure controlcamera, if the camera shutter is released by means of the body releasebutton 56, the blade opening member 1 will be driven clockwisely,similarly as in the case of the automatic exposure control camera, andthe diaphragm blade opening ring 3 and the first diaphragm actuatingmember 7 will be caused by their respective springs 6 and 9 to follow upthis movementto begin a return movement in the clockwise direction. As

shutter blades for the purpose of exposure.

tion and controls the diaphragm blades or so that they form a diaphragmaperture corresponding. to the diaphragm value preselected at the finalposition of the rotation of the first diaphragm actuating member 7. Thecontrol movements of the diaphragm blades 64- are achieved by aconstruction wherein, in the case of each blade, a pin 65 on one sidethereof is engaged with a circular hole lllb in one of the two diaphragmactuating members 7 and 9, and the pit-1 66 on the other side is engagedwith a cam slot 7b of an obtuse V shape in the other diaphragm actuatingmember, one portion of the said slot 7 bextending substantially along anarc of a circle which is concentric with the said diaphragm actuatingmember, and the remainder portion of the said slot 7b it will beapparent from the detailed description pre: sented above of theprinciple and embodiment of the present invention that the severalobjects set forth in the beginning of this disclosure and theaccompanying advantages can be achieved by a simple construction and,moreover, in a sure manner. Furthermore,.from the embodiment applied tothe interchangeable lens type, singlelens reflex camera ofthisinvention, the following points will be understood readily andsimply.

If the cooking of the main drive device andthe blade opening member 1 oftheshutter are intercoupled and so adapted as to take placesimultaneously, itwill be possible to provide a conventional,interchangeable lens type,

single-lens reflex camera wherein, through the operation of the bladeopening member 1, the diaphragm blades are.

fully opened similarly as are the shutter blades, and focal adjustmentthrough the lens system is possible only at the time of the cocking ofthe shutter. (The simultaneous cooking of the shutter and the feeding ofthe film in many of the cameras produced at present is well known in theart. Accordingly, in many cases, the cocking of the manner as theshutter blades, it is. possible to provide a single-lens reflex cameraof interchangeable lens, quickreturn type wherein focal adjustment ispossible through the lens system irrespective of the sequence, prior toor after, the cocking of the shutter.

It will be obvious, furthermore, that by severing the relationshipbetween the blade opening member '1 and the device which additionallyopens and closes the shutter blades (the device which until now has been[referred to in the foregoing description as the intermediate de- Vice(not shown))-, it is possible to provide an ordinary, interchangeablelens type camera, which is not of the single-lens reflex type, andwherein the cocking of the blade opening member 1 merely fully opensonly the dia- Then the 9 phragm blades 64 and thereafter operates asdescribed in detail above, the shutter speed and diaphragm value can beselected manually,. and automatic control of the diaphragm is possible.

While the above description has related to an interchangeable lens typecamera, the invention may be applied also to a camera ofnon-interchangeable lens type. For example, in the diagramof FIG. 1indicating the principle of the present invention, such a camera may beconstructed by assembling in the shutter two diaphragm actuating members7 and '10 and diaphragm blades 64 which aresupported controllably by thesaid members; constructing the diaphragm blade opening member 3 and thefirst diaphragm actuating member 7 as an integral body, or engaging andcoupling the forwardly extending lug of the said member 3 to a portionof the diaphragm actuating member 7, recessed from the outer edgethereof, for example, a cut-out recess; engaging and coupling theforwardly extending lug 15 of the diaphragm scale ring 14 to a portionof the pawl 11 of the second diaphragm actuating member 10, recessedfrom the outer edge thereof, for example, a cut-out recess; and deletingthe pawl 8 of the diaphragm actuating member 7 and the springs 9 and 13of the diaphragm actuating members. It will be apparent that even withthis simple construction, since the two diaphragm actuating members 7and 10 perform the same operations as previously described, the sameoperational effect isachieved, and, accordingly, it is possible toprovide a camera with automatic exposure control.

However, since one embodiment of the inventionis of the interchangeablelens type, the relationships of the pawl 8 and pawl 11 of the first andsecond diaphragm actuating members 7 and 10 to the forwardly extendinglugs 5 and of the diaphragm blade opening member 3 and diaphragm settingring 14, respectively, at the time of lens changing will be madeapparent by the following detailed description. I

Of the three illustrations, FIGS. 7, 8, and 9 FIG. 7 indicates thecondition wherein the diaphragm actuating mechanism consisting of thesetwo diaphragm actuating members 7 and 10 is installed between theoptical system 62 and 63 of the interchangeable lens assembly 60; thisinterchangeable lens assembly, by means of the bayonet lug 61 thereon,is connected to the bayonet mount 53 of the camera body; and the springs9 and 13 are caused to function on their respective diaphragm actuatingmembers 7 and '10 so that the pawl 8 and pawl 11 of'the said respectivediaphragm actuating members are correlated, respectively, to theforwardly extending lugs 5 and 15 of the diaphragm blade opening member3 and diaphragm setting ring 14 on the body side. This explains how,even when the interchangeable lens are each connected to the camera bodywith a certain rotational angle, the two pawls 8 and 11 and theforwardly extending lugs 5 and 15, which constantly occupy mutuallydifferent positions, are maintained in mutual correlation by the springs9 and 13 which impart tension on the two diaphragm actuating members 7and 10. Furthermore, it is necessary to establish a relationship of thecorrelation respectively between the two pawls 8 and 11 and theforwardly extending lugs 5 and 15 to the state of the interchangeablelens side corresponding to the various conditions due to theopenation ofthe diaphragm actuating mechanism on the camera body side (automaticcontrol or manual control, or prior to or after the cocking of bladeopening member). The following is a description of this relationshipwith ref.- erence to FIGS. 10 through 13.

FIG. 10 indicates the condition wherein the camera. has

been switched to automatic control, and the interchangeable lens 60 hasbeen connected to the camera body prior to the cocking of the bladeopeningmem-ber. In the general case of bayonet mounting, it is commonpractice to adapt the mount so that, by mounting the lens side androtating it from 50 to 60 degrees, it is held positively.

10 Accordingly, if at the time the lens is mounted in the case of FIGS.1 and 10, the pawls 8 and 11 of the first and second diaphragm actuatingmembers occupy, respectively, the posit-ions 8a and 1111, said pawls 8and 1'1 will obviously be caused by the subsequent, clockwise rotationof the lens (rotation of angle 0 indicated in FIG. '10) to be in thepositions 8b and 1111, respectively. However, the pawl 8 engages withthe forwardly extending lug 5 of the diaphragm blade opening member 3 atthe terminal position of rotational angle of the lens, and the pawl 11,on one hand, is prevented by the forwardly extending lug 15 of thediaphragm setting ring 14 to rotate together with the lens, and merelystretches the spring 13. It will be understood, therefore, that as aresult, the pawls 8 and 11 possess mutual correlation .due to,respectively, the forwardly extending lugs 5 and 1-5 by the springs 9and13 and are in accordance with the principle indicated in FIG. i1.

FIG. 11 indicates the condition wherein the camera has been switched toautomatic control, and the interchangeable lens 60 has been connected tothe camera body after the cocking of the blade opening member. When thelens is mounted under these conditions, the pawls 8 and 11 of the firstand second diaphragm actuating members occupy the positions 8a and 11aand, together with the clockwise rotation of the lens, engage with thefor Ward-1y extending lugs 5 and 15 of the diaphragm blade openingmember 3 and diaphragm set-ting ring 14 thereby being stopped.Thereafter, the said pawls stretch the springs 9 and 13 of the first andsecond diaphragm actuating members. Accordingly, it is obvious that theyare in accordance with the principle indicated in FIG. 1.

FIGS. 12 and 13 indicate the conditions wherein the camera has beenswitched to manual control, and the interchangeable lens '60 has beenconnected to the camera body prior to and after the charging of theblade opening member. It will be seen that, in both of these cases, thepawls 8 and '11 of the respective diaphragm actuating members engagecorrelatedly with the forwardly extending lugs 5- and 15, similarly asin the cases illustrated FIGS. 10 and 11,

The above relationship may be represented more mathematically by thefollowing representations in which:

0, denotes the angle of rotation of the lens required for attachment anddetachment;

0 denotes the range of adjustment of diaphragm, being, in

the present embodiment, from Fz2 to P22;

0;; denotes the angle of rotation by which the diaphragm setting ringexceeds the diaphragm adjustment range 6 that is, the minimum angle ofrotation of the diaphragm setting ring necessary for switching frommanual to automatic control, or in reverse, from automatic to manualcontrol; and

0 denotes the cocking angle of the blade opening member.

Then, in the present embodiment,

1 3-l' 2 and 1 4 however It will be seen, therefore, that irrespectiveof the posi tions of the two forwardly extending lugs '5 and 15 from thecamera body side and the pawls 8 and =11 of the lens side, :the tworespective combinations engage without mutual collision, and theprinciple of the present invention is satisfied.

It will be readily seen that, while the above detailed description hasrelated to the case of an .ordinary,- singlelens reflex camera, thepresent mechanism may be used directly, as it is, also to cameras of thequick-return, single-lens reflex type wherein the shutter and diaphragmblades reopen. In this case, the conditions of FIGS. 10

land 12 do not exist except when the opening and closing of the shutterblades take place on the camera side for the purpose of exposure. Thatis, since the diaphragm blade opening member 3 and the blade openingmember '1 are constantly maintaining the shutter and diaphragm blades intheir opened condition, only the states of FIGS. 11 and 1-3 *exist. V

. Furthermore, by the application of this invention it is possible toprovide a camera with automatic exposure control wherein the exposure isautomatically controllable in even a more positive and simple manner asis described 'below. In the ease of a camera capable of automaticcoupling with an exposure meter, wherein the mechanism range of exposureadjustment corresponding to exposure time (shutter speed) of the orderof B, 1 to /500 second in 1:1 stages and diaphragm adjustment of theorder of R2 to F:-22 in 8 stages are most commonly used.Accordingly,-since a difference exists between the measurement range oftheexposure meter and the exposure adjustment range of the camera,ranges wherein adjustment by means of the exposure meter cannot be madeoccur unavoidably. Furthermore, in the case wherein the exposure time(shutter speed) is selected beforehand, and the diaphragm aperture isautomatically controlled by an exposure meter, photography at lowshutter speed tends to cause shaking of the camera, whereby thisexpedient is undesirable. :These problems can be solved by attaching alimiting device which limits the range of adjustment of the shutterspeed, and so adapting the camera that, :in the case of manual selectionof exposure, the said limiting device does not engage, and the entirerange of exposure adjustment possessed by the camera can be used; and inthe case of selecting the exposure time (shutter speed) beforehand andautomatic controlling of the diaphragm aperture by meanslof an exposuremeter, the said limiting device is have tendencies of rotating clockwiseand counterclock wise, respectively, is disposed between the diaphragmsetting ringl14 and the shutter speed setting ring 17. One end of thisdevice 70 is provided with a tooth 71 which enin FIG. 14; the tooth 7 1on one end of the limiting device" 70 will be caused by the spring 75 tobe in elasticallymaintained contact with the notch 76 of the diaphragmsetting ring; the tooth '72 on one side of the other end'will disengagefrom the limit slot 77 and the tooth 73 on the other side will engagewith the clearance hole '78 of the shutter speed setting ring. Underthis condition, the

diaphragm setting ring 14, that is, the mark A, is held fixed by thenotch 7 6' and tooth 7 1 in elastically-maintained contact, while theshutter speed setting ring 17 is able to rotate freely within the rangedetermined by the limiting action of the tooth 73 on the two ends of theclearance hole 7 8. This range of rotation becomes the high-speed scalerange (for example: to second), and it becomes impossible to bring ascale range of any lower speeds (for example to 1 second and bulb) tocoincide In other words, the'selection of exwith the index 16b. posuretime (shutter speed) of the camera at the time of automatic exposurecontrol is restricted within the high speed range.

When an attempt is made to bring the automatic operation mark A of thediaphragm setting ring 14 to coincide with the index 16]) in order toswitch the camera to automatic exposure control, if the said index 1617,at the time, is confronting and coinciding with the low-speed scalerange (for example: to 1 second [and bulb) of the shutter speed settingring 517, the tooth 7.2 on one side of the other end of the limitingdevice 70 engages with anend of the limit slot 77, as illustrated inFIG. 15, and the tooth '73 on the other side separates from theclearance hole78, thereby blocking the rotation of the diaphragm settingring 14- and, at the same time, enabling the shutter speed setting ring17 to rotate freely. Accordingly, the 1 automatic operation mark A isrendered incapable of coinciding with the index 16b, while theadjustment of the shutter speed setting ring 17 over the entire speedrange with respect to the index 16b becomes possible. Accordingly, inthis case, the camera is selectively used either in gages a notch 76 inthe diaphragm setting ring 14. The I other end of this device 71 isprovided on one side with a tooth '72 which engages with a limit slot 77on the diaphragm setting ring 14 and on the other side with a toothrange (for example: 6 to 4 second) of the shutter speed setting ring 17,the automatic operation mark A will be able to coincide with the saidindex 161) as shown the condition of manual control or in the conditionof automaticcontrol by moving the high-speed scale range of the shutterspeed setting ring 17 towards the index 1612, then bringing theautomatic operation markA to coincide with index 16b. V

FIGS. 16 and 17 illustrate another embodiment of the limiting device forthe switching between the automatic coupling and manual adjustment shownin the abovementioned FIGS. 14 and 15. In this'embodiment, the tooth 72on one side provided on the other end of the limiting device 70 of theprevious embodiment has been omitted, and, in its place on the device70, a tooth 7212, which is slideable in an elastic manner relative tothe said device, is provided so as to engage with the limit slot 77. IThat is, the tooth 72b slides elastically relative to the device 70through the engagement of a slot hole 79 formed in the base portion ofthe said tooth 72b with the pin portion of a screw 80 which holds thesaid base portion to the device 70 and through the tension of a spring3-1.

FIG. 16 illustrates the condition wherein, upon the per 7 formance ofexactly the same operation as shown in FIG. 14 of the previousembodiment, it is possible to bring the automatic operation mark Aimmediately to coincide with the index 16b when the high-speed range ofthe shutter speed scale is confronting the index 16b. Therefore, thecamera is an automatically-coupled camera wherein only the high-speedscale range can be freely selected.

FIG. 17 illustrates a mechanism, the operation of which is somewhatdifferent from that of the case shown in FIG.

the end of the device 70, and which is engaged with the said end edge,to move in unison against the force of the spring 81. Accordingly, ifupon bringing the automatic operation mark A to coincide with the index16b, the hand is removed from the diaphragm setting ring 14, the saidtooth 72b will be returned by the tension of the spring 81, and thisreturning force will cause the tooth 72b to move the aforesaid end edgeof the limit slot 77 to move with it in the reverse direction, therebyreturning the diaphragm setting ring 14, that is, the automaticoperation mark A, to theoriginal position. Consequently,'it becomesimpossible to place the automatic operation mark A in coincidejnce, withthe index 16b. Therefore, when the'camera is in this condition, it isused in this condition by manual adjustment or it is used after it 'hasbeen switched to automatic coupling by first placing the high-speedrange of the shutter speed scale in coincidence with the index 16b, thensetting the automatic operation mark A in coinc'idence with the index16b, this procedure being the same as that of the preceding embodiment.In the case of the present embodiment as shown in FIG. 17, it is notnecessary to rotate the diaphragm setting ring 14 against the limitingdevice 70 with as great a force as in the preceding case shown in FIG.15 in order to switch the camera to automatic control; therefore, thecamera mechanism is protected.

It will be seen from the foregoing detailed description of embodimentsof the present invention that they amply achieve the objects of theinvention. That is, a oamera capable of automatic control of thediaphragm aperture in accordance with the exposure time (shutter speed),corrected sensitivity (corrected for film exposure index, filter factor,etc.), brightness of the object to be photognaphed, and other factors isobtained. Moreover, through a blade opening member, diaphragm bladeopening member, and two diaphragm actuating members, the camera becomes:a single-lens reflex camera capable of automatic coupling with anexposuremeter, and since the mechanism for automatic coupling with anexposure meter is switched by severing the link between the diaphragmblade opening member and the coupling cam provided to confront theexposure meter pointer, a camera wherein, by this switching, it ispossible to use freely both automatic exposure control and manualadjustment of the exposure is obtained. Furthermore, when the diaphragmblade opening member, the diaphragm scale ring, and the two diaphragmactuating members are linked in a follow-up manner by the use ofsprings, it becomes possible to provide an interchangeable lens typecamera wherein automatic coupling with an exposure meter is possible,and wherein the switching of the camera to automatic exposure controlcannot be accomplished in the low-speed range of the exposure time(shutter speed) and can be accomplished in only the high-speed range.-

Furthermorc, it is possible to adapt the mechanism so that once thisswitching has been accomplished, the use of the camera thereafter ispossible only in the highspeed range of the exposure time.

Since it is obvious that many changes and modifica- ,tions can be madein the above described details'without departing from the nature andspirit of the invention, it is to be under-stood that the invention isnot to be limited to the details described herein except as set forth inthe appended claims.

What I claim is:

1. In a photographic camera of the type having a pl1otographlc ens, abuilt-in exposure meter, an adjustable diaphragm means including bladesthat can be opened and closed and an adjustable speed shutter, a shutteropening member carrying a lug, a diaphragm blade opening member having aforwardly extending lug, said diaphragm blade opening member beingbiased for rotation in one direction about the optical axis of the lens,a latching pawl on said diaphragm blade opening member to be contactedby said lug on said shutter opening member, a first diaphragm actuatingmember biased for rotation similar to the rotation of said diaphragmblade opening member, a pawl on said first diaphragm actuating member tobe contacted by said forwardly extending lug on said diaphragm bladeopening member, "a second diaphragm actuating member, said blades beingsupported by and between said first and said second diaphragm actuatingmembers whereby relative rotation of said diaphragm actuating membersactuates said diaphragm blades, means to bias said second diaphragmactuating member for rotation in the same direction as the bias of saidfirst diaphragm actuating member, a pawl on said second diaphragmoperating member slid'able a predetermined distance circumferentially ofsaid second diaphragm actuating member and biased in the direction ofbias of said second diaphragm actuating member, a diaphragm setting ringprovided with a lug for engaging said biased pawl on said seconddiaphragm actuating member to arrest the rotation of said seconddiaphragm actuating member, a shutter speed setting ring, detent notchesin said shutter speed setting ring, a correction ring for correcting thesetting of the built-in exposure meter in accordance with thephotographic factor of the film being used in the camera and a filterfactor, said correction ring carrying a click detent to engage thedetent notches in said shutter speed setting ring, a cam surface on saidcorrecting ring, a cam follower biased against said cam surface on saidcorrecting ring and drivingly connected to said camera shutter, wherebyspeed of said shutter is controlled, gear teeth mounted on saiddiaphragm blade opening member, a shaft parallel to the optical axis ofsaid camera, a coupling gear secured to said shaft and meshing with saidgear teeth, clutch means operated by said shaft, a cam stop plate forcooperating with said exposure meter to secure the setting of saidexposure meter, rack and pinion means to move said cam stop plate, saidclutch means selectively connecting said shaft and said pinion, said camstop plate being of the type the movement of which is stopped by thepointer of said exposure meter, a cam surface on said diaphnagm settingring, and a clutch actuating rod engaging said cam surface on saiddiaphragm setting ring whereby, upon moving said diaphragm setting ringto a predetermined position, said clutch is en-gagedto render theoperation of the diaphragm automatically dependent on the exposuremeter.

2. In a camera, in combination, an exposure meter, a movable stop memberthe position of which is determined by said exposure meter, a step-cammovable toward said movable stop member to sense the position of saidstop member and therefore to sense the setting of said exposure member,diaphragm means including a plurality of diaphragm blades and tworelatively rotatable plates 1 between which said blades are mounted andby relative rotation of which the diaphragm opening is determined, adiaphragm blade opening member, coupling means by which said bladeopening member is coupled to said step cam, whereby said diaphragmopening is, automatically adjusted, and a diaphragm setting ring, aclutch means interposed in said coupling means whereby said diaphragmblade opening member may be uncoupled from said step cam means, a camsurface on said diaphragm setting ring, and means operated by said camsurface on said diaphragm setting ring whereby said clutch means may beselectively engaged or disengaged.

3. In a photographic camera of the reflex type having a shutter thatmust be cocked and in which the diaphragm opening is controlled by tworelatively rotatable diaphragm actuating members from and between whicha plurality of diaphragm blades are suspended and in which the first ofsaid rotatable diaphragm actuating members is operated by cocking theshutter mechanism to open the diaphragm for use of the camera lens as aview finder, and the second of said members is engaged by a diaphragmsetting member, an exposure meter, sensing means by which thedetermination of illumination made ting said second diaphragm actuatingmember, and means operated by said cam means to disengage said clutchWhen said means for manually setting said second diaphragm actuatingmember is moved into the range of manualsettings from a position Wherethe clutch is engaged to provide for automatic control of the diaphragmopening. a

References Cited in the file of this patent UNITED STATES PATENTS2,913,969 Faulhaber N0v.'24, 1959 2,935,921 Rentschler May 10, 19602,943,545 Fahlenberg July 5,' 1960 2,969,004 Gebele Jan. 24, 19612,974,518 Wittel Ma'r.j14,,1961j 3,013,478

Gebele Jan. 13, 1959 Gebele Decl 119, 1 9 61

2. IN A CAMERA, IN COMBINATION, AN EXPOSURE METER, A MOVABLE STOP MEMBERTHE POSITION OF WHICH IS DETERMINED BY SAID EXPOSURE METER, A STEP-CAMMOVABLE TOWARD SAID MOVABLE STOP MEMBER TO SENSE THE POSITION OF SAIDSTOP MEMBER AND THEREFORE TO SENSE THE SETTING OF SAID EXPOSURE MEMBER,DIAPHRAGM MEANS INCLUDING A PLURALITY OF DIAPHRAGM BLADES AND TWORELATIVELY ROTATABLE PLATES BETWEEN WHICH SAID BLADES ARE MOUNTED AND BYRELATIVE ROTATION OF WHICH THE DIAPHRAGM OPENING IS DETERMINED, ADIAPHRAGM BLADE OPENING MEMBER, COUPLING MEANS BY WHICH SAID BLADEOPENING MEMBER IS COUPLED TO SAID STEP CAM, WHEREBY SAID DIAPHRAGMOPENING IS AUTOMATICALLY ADJUSTED, AND A DIAPHRAGM SETTING RING, ACLUTCH MEANS INTERPOSED IN SAID COUPLING MEANS WHEREBY SAID DIAPHRAGMBLADE OPENING MEMBER MAY BE UNCOUPLED FROM SAID STEP CAM MEANS, A CAMSURFACE ON SAID DIAPHRAGM SETTING RING, AND MEANS OPERATED BY SAID CAMSURFACE ON SAID DIAPHRAGM SETTING RING WHEREBY SAID CLUTCH MEANS MAY BESELECTIVELY ENGAGED OR DISENGAGED.